Chuck and grinding wheel



Dec. 8, 1942. c. E. HITE 2,304,173

CHUCK AND GRINDING WHEEL Filed May 23, 1940 y 1/1141 6AM Hiram Patented Dec. 8, 1942 UNITED STATES PATENT OFFICE 2,304,173 cnocx AND GRINDING WHEEL Charles E. Hite, Philadelphia, Pa., asslgnor to Lewis J. Musser, Newtown, Pa.

Application May 23, 1940, Serial No. 336,877,

4 Claims.

The present invention relates to chucks for holding wheels and disks and that more usually are intended for holding grinding wheels and disks when operating upon th wheels and disks in manufacture and subsequently when using them selectively for grinding or facing operations, and the invention relates to wheels and disks, particularly with respect to the mounting portions thereof that cooperate with chuck structures, the invention being in part divisional from the applicants application for Centrifugal chuck, Serial No. 231,175 filed September 22, 1938, .and allowed January 29, 1940.

The terms wheel and grinding wheel as used herein are intended to apply broadly not only to disk grinding wheels, cup and cone'grinding wheels, and facing and sanding plates but also to any similar device adapted to be held by the mechanism of the present invention.

A purpose of the invention is to grip a grinding wheel or wheel mount centrifugally when rotation starts.

A further purpose is to adapt holding jaws having a small range of radial movement to use with wheels over a relatively wide range of sizes.

A further purpose is to accommodate the character of engagement between a jaw and a wheel gripp d by the jaw to the needs of service. Thus, when used for holding wheels on a machine for facing and trimming wheels the torsion upon the gripped wheels is much less and much more uniform than when the wheel itself is in grinding service for which reason in the one case the jaw surface presented to the wheel may be either arcuate to fit the wheel curvature or flat to engage the wheel tangentially while in the other case I may provide a radial interlocking of the jaw and wheel, for example, the jaws may present pins into sockets of the wheel or vice versa, and particularly in the case of cup and cone wheels I may provide the wheel and jaws with reversely flaring engagement surfaces, a downward flare of the jaw ends fitting against an upward flare of the wheel.

A further purpose is to grip a cylindrical cup wheel having a downwardly flaring base with jaw surfaces flaring upwardly to fit the downward flare of the base. a

A further purpose is to form a cylindrical cup wheel with a downwardly flaring base for presentation to upwardly flaring jaw surfaces of preferably centrifugally operated chuck jaws.

A further purpose is to provide a bi-part metal base for use with cone cup wheels converging downwardly, flaring the upper part of the base upwardly to fit the interior conical surface of the wheel, preferably flaring the lower part Of the base downwardly for engagement by correspondingly upwardly overhanging jaw surfaces, and clamping the wheel to its base in removably fastening the base parts together.

Further purposes will appear in the specification and in the claims.

I have elected to illustrate a number only out of, the many forms of my invention, selecting forms however that are practical and efficient in operation and which well illustrate th principles involved.

Figures 1 and 2, in broken top plan and broken sectional elevation respectively, are intended to illustrate conventionally mechanism embodying the present invention and to show a wheel or wheel mount held by a plurality of chuck jaws (three in the figures) of any suitable form and gripping by the centrifugal action of any suitable mechanism within the body of the chuck. Figure 2 is a section of Figure 1, on the line 2-2 thereof.

Figures 3, 4 and 5 are fragmentary sectional elevations intended to illustrate somewhat difierent arrangements at the wheel and jaw with somewhat different types of wheel, in each case the jaw being intended to operate centrifugally in any suitable way, optionally as in Figure 2 with minor structural changes.

Figur 6 is a fragment left elevation of Figure 2.

Like numerals refer to like parts in all figures.

Describing in illustration and not in limitation and referring to the drawing:

In Figures 1 and 2, a wheel I5 on a three-part base 46, 41, 48 is held by the jaws l6 of a chuck l'l upon a spindle l8 of any suitable machine beyond the spindle, the jaws radially gripping and longitudinally overlapping the wheel. This machine may be, for example, one for facing and trimming unfinished wheels, or it may be a grinding machine for using different wheels selectively for grinding, or it may be any mechanism for suitably rotating the spindle.

An operator using my chuck on a machine for facing and trimming unfinished wheels normally operates upon wheels of different standard commercial sizes, first upon a succession of wheels of one size, then upon a succession of wheels of another size, and so on with wheels of other sizes, changing the wheel each time rotation ceases and at intervals changing the setting of the chuck to accommodate a different size (diameter) of wheel.

With my chuck on a grinding machine, an operator with some classes of work may not change the wheel over many periods of rotation and in other classes of work selects his wheel to suit the work, often using one wheel for initial rough grinding, with all of the wheels probably more usually being of the same commercial size but sometimes of different sizes, particularly if the spindle I8 is to operate selectively at different speeds or it the chuck is to be used selectively on different spindles of difierent speeds.

When the chuck is rotating centrifugal action of mechanism within the chuck causes that mechanism to press the jaws radially inward upon the wheel or wheel base, gripping the wheel by the centrifugal action of the mechanism within the chuck.

When rotation of the chuck stops the centrifugal action also stops and I intend the grip of the jaws upon the wheel or wheel base'then selectively automatically to release or, under the action of jaw-holding mechanism, to maintain until the operator releases the jaw-holding mechanism.

When the operation is to be with a succession of wheels, as one wheel l5 during each period of rotation and a diflerent wheel l5 during the next period of rotation, I intend the jaws to release and open automatically as the rotation stops, and the degree or opening preferably then to be merely that permitting an easy and rapid change of wheels.

Each time rotation starts after changing one wheel for another the somewhat retracted jaws l6 move inward coordinately upon the inserted wheel l5, centering it and gripping it at its base 48.

When the chuck is to hold a wheel for heavy duty grinding I may provide a pin-and-socket interlocking between the wheel and each jaw, for example, as indicated in Figure 5, where each jaw I8 presents a metal pin 4! into a socket 42 formed in the wheel is. This pin-and-socket interlocking of the wheel and chuck jaws eliminates any danger of rotational slippage between the wheel and chuck during heavy duty service and greatly lessens the needs for gripping engagement between the wheel and chuck during periods of non-rotation; this is particularly true in that I provide means for limiting the degree of jaw opening to any desired value that optionally may be made substantially zero.

More usually any pin-and-socket interlocking of the wheel and chuck jaws is unnecessary in that I may dimension the parts to secure any desired gripping of the jaws upon the wheel, but the pin-and-socket interlocking may become desirable when the wheels are to be used in nonhorizontal positions, particularly if the wheels are cylindrical or cone cup wheels and are to be subjected to heavy stresses tending to pull the wheel both axially and laterally away from the chuck.

I intend to provide a cylindrical cup wheel, such as 43, Figure 4, with a base portion 44 having an outside downward flare and to provide chuck jaws I8 with a corresponding upward and inward flare, an inwardly directed overhanging portion 45, to fit the downward and outward slope of the base.

In Figure 3 I show a cup wheel 43' having a base 44' inwardly converging downward and for each size of this type of wheel I provide a threepart base, a lower part 46' adapted to be held by the jaw iii of my chuck, an upper part 41' fitting the interior of the converging base 44' of the cup wheel at a portion thereof slightly above the base 48' and a central screw 48' removably clamping the upper and lower parts and cup wheel together. As shown the screw 48' has a downward extension 49 of reduced diameter into the center bore 40 of the chuck.

It will be seen that each cup wheel may be used up in service down to the upper part 41' of my composite base and that the stub may be then taken off the base by unscrewing the screw 48' and a new cup wheel of the same interior size then mounted on the composite base in place of the used up wheel. In Figure 3 the chuck jaw l6 presents-a somewhat overhanging surface at 45 to the somewhat downwardly outwardly sloping periphery of the base 46'.

In Figures 1 and 2 a cone cup wheel I! is shown mounted upon my composite base, the upper part 41 fitting the interior of the cup wheel a little above the base 46 and cooperatively with the screw 48 clamping the wheel to the lower base 46, with the reduced end 49' of the screw centering the composite base and wheel in fitting into the center bore 40' of the chuck. The lower part 46 of the composite base and the chuck jaws present suitable longitudinally interlocking surfaces one to the other, an overhanging jaw surface 45 engaging the corresponding downwardly flaring periphery of the base part 46.

Whenever my chuck is intended to be used exclusively with cup or other wheels intended to be mounted in service upon a base having a centerimg pin 48 or 49' in a center bore 40 or 44' of the chuck, other means for equalizing the radial movements of the diflerent jaws optionally may be omitted.

In the structure of Figures 1 and 2 the jaws are radial slides, each jaw l6 sliding iri a radial inverted T slot with lateral runners of the jaws sliding in lateral runway portions of the slot. On its under side the jaw is provided with a succession of upward recesses 69 to receive selectively the upper end of an operating bolt or pin 56 presented from a centrifugally operated hub 83 and adapted to be pulled downward into the hub out of the recess to permit shifting of the jaw to receive the operating pin 56 selectively in any of the recesses 69.

Each operating member of a jaw includes the pin 56 and an integral diametral slide comprising the hub 83 carrying the pin 58, a weight 51 diametrially opposite the hub 83 and a web or plate 84, 85 or 88 connecting the weight and hub and centrally slotted at 81 topass the hub 59 of the chuck.

The pin 56 is illustrated as maintained in its operating position by a flat spring 10, one carried by each of the plates 84, 85 and 88, with minor modification of the mountings to best adapt it to the somewhat different locations of the plates.

As shown, the end of the spring 10 underlaps a shoulder I04 of the pin 5|. When it is desired to change the setting of the jaws the pins I are pulled downward by a suitable tool after which the jaws are slid to the desired setting.

Each weight 51 is provided with an upward lug 90 within a radial guideway slot 8| of the chuck body and at the diametrially opposite side of the chuck the hub" slides in a radial guideway 92, and the operating mechanisms of the diflerent jaws, as illustrated, are intended to differ merely in the location of the plates 84, 88 and 86 with respect to the hub and weight members 83 and 81 at their diametrially opposite ends. the plates 84, 8B and 88, angularly spaced 120 degrees being located successively one above and against another.

Each weight 51 is provided with a cam slot III'I which receives the upwardly projecting end of a pin I08 rigidly mounted in a retraction plate I09, the lower end of the pin I08 extending downwardly to adjustably limit the retraction, the opening movement of the chuck, by engaging a cam edge H of a stop plate Ill angularly ad- Justable on the hub 59 of the chuck.

A torsion spring H2 surrounding the hub 59 has its ends H3 and H4 extending into the hub 59 and the retraction plate I09 respectively, the resulting torsion on the plate being in direction to pull the weights 51 radially inward by means of the upper end of the pins I08 in the cam slot ill! of the respective weights, thereby retracting the jaws outwardly.

The screw Iliil'has a taper body at H5 adapted to clamp against the sloping edges H6 of a slot iiii in the hub 99 of the stop plate lil, thereby permitting peripheral adjustment of the plate upon loosening this screw, shifting the plate to the desired position and then retightening the screw, to adJusta-bly set the retraction of the chuck jaws. A collar ill fastened to the hub 59 cooperatively with the torsion plate 109 and the stop plate ill at the set screw I00 may conveniently carry the weight of the operating mechanism.

In view of my invention and disclosure variations and modifications to meet individual whim or particular need will doubtless become evident to others skilled in the art, to obtain all or part of the benefits of my invention without copying the structure shown, and I, therefore, claim all such in so far as they fall within the reasonable spirit and scope of my invention.

Having thus described my invention what I claim as new and desire to secure by Letters Patent is:

1. A chuck for holding a grinding wheel having a irusto-conical upwardly converging base and the, chuck comprising a chuck body, weight means mounted in said body adapted to move outwardly with respect to the axis of the said body under the influence of centrifugal force when the chuck is rotated. Jaws having upwardly converging inward surfaces presented to the upwardly converging base adapted to clamp the base upon the body. means connecting said weight means and said jaws in such manner as to cause the jaws to move inwardly toward the axis of the chuck as the weight moves outwardly. away from said axis and thereby clamp a wheel base placed between the Jaws.

2. A cup wheel interiorly converging downwardly near its lower end, a frusto-conical upwardly converging base under the wheel and coaxial therewith, a disk inside the wheel near the lower end of the wheel fitting the downwardly converging wheel interior and a screw engaging the disk and base to hold the base, the wheel, the disk' and the screw coaxial in a rigid unit for cooperative use with a wheel chuck comprising a chuck body, weight means mounted in the body adapted to move outwardly with respect to the axis of the body under the influence of centrifugal force when the chuck is rotated, jaws having upwardly converging inward surfaces adapted to clamp the base upon the body and means connecting said weight means and said Jaws in such manner as to cause the jaws to move inwardly toward the axis of the chuck as the weight moves outwardly away from said axis and thereby clamp a wheel base placed between the Jaws.

3. A frusto-conical upwardly converging base for use under a cup wheel having an interior converging downwardly near its lower end, a disk to fit inside the wheel in the converging portion and a screw engaging the disk and base to hold the base, the wheel, the disk and screw coaxial in a rigid unit for use with a wheel chuck comprising a chuck body, weight means mounted in said body adapted to move outwardly with respect to the axis of the body under the influence of centrifugal force when the chuck is rotated, jaws having upwardly converging inward surfaces presented to the upwardly converging base to clamp the base upon the body, means connecting said weight means and said Jaws in such manner as to cause the jaws to move inwardly toward the axis of the chuck as the weight moves outwardly away from said axis and thereby clamp a wheel base placed between the jaws.

4. A frusto-conical converging base for use under a cup wheel having an interior converging downwardly near its lower end, a disk to fit inside the wheel in the converging portion, a screw engaging the disk and base to hold the base. the wheel, the disk and the screw coaxial in a rigid unit for cooperative use with a wheel chuck, the screw having a downward extension for registry in a center bore of the chuck and the chuck comprising a chuck body, weight means mounted in said body adapted to move outwardly with respect to the axis of the said body under the influence of centrifugal force when the chuck is rotated, jaws having upwardly converging inward surfaces presented to the upwardly converging base adapted to clamp the base upon the body, means connecting said weight means and said jaws in such manner as to cause the jaws to move inwardly toward the axis of the chuck -as the weight moves outwardly away from said axis and thereby clamp a wheel base placed between the Jaws. v I

CHARLES E. Hfl'lE. 

